Field
Embodiments of the invention relate to electronic systems, and in particular, to charge pumps for radio frequency systems.
Description of the Related Technology
Charge pumps can be included in a variety of electronic systems. For example, an integrated circuit (IC) may be powered using a power high supply voltage and a power low supply voltage, and the IC can include one or more charge pumps for generating a charge pump output voltage above the IC's power high supply voltage and/or below the IC's power low supply voltage.
In one example, a wireless device can include RF switches that are controlled in part using a charge pump voltage generated by a charge pump. For instance, a charge pump can be used to generate a negative charge pump voltage for biasing the gate voltage of one or more n-type metal oxide semiconductor (NMOS) switch transistors when operating in an off state. Controlling the gate voltage of an NMOS switch transistor to a voltage below a power low supply voltage can increase off state impedance, which can enhance isolation and/or improve harmonic performance in multi-band applications.
There is a need for improved charge pumps.